Some machines have a ride control system that is hydraulically coupled with other hydraulic systems, for example a loader or boom system. In these and similar machines, it is desirable to have pressure equalization between the ride control system and the coupled hydraulic systems prior to ride control activation. By matching the pressure between the ride control accumulators and the pressure in, for example, the boom cylinders any unintended raising or lowering motion in the boom can be avoided or reduced when ride control is engaged.
It would be desirable to have the ride control system designed to perform one or more of the following functions: (1) to equalize the pressure between the head side of the loader cylinder and the ride control cylinders, (2) to provide a low pressure drop connection between the head side of the loader boom cylinder and the cushioning volume in the ride control accumulators, and (3) to provide a low pressure drop connection between the rod side of the loader boom cylinder and tank. It would also be desirable to have the ride control system perform some auxiliary functions, which could include: (1) to provide a mechanism for dead engine lower, (2) to provide a mechanism for safely discharging the pressure in the ride control accumulators, and (3) to provide condition monitoring of the ride control accumulators.